6645341556736 has 117 divisors (see below), whose sum is σ = 13593684480709. Its totient is φ = 3248181051392.

The previous prime is 6645341556599. The next prime is 6645341556757. The reversal of 6645341556736 is 6376551435466.

It is a happy number.

The square root of 6645341556736 is 2577856.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6158338560000 + 487002996736 = 2481600^2 + 697856^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 7754190420 + ... + 7754191276.

Almost surely, 2^{6645341556736} is an apocalyptic number.

6645341556736 is the 2577856-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6645341556736

6645341556736 is an abundant number, since it is smaller than the sum of its proper divisors (6948342923973).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6645341556736 is an frugal number, since it uses more digits than its factorization.

6645341556736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1832 (or 906 counting only the distinct ones).

The product of its digits is 163296000, while the sum is 61.

The spelling of 6645341556736 in words is "six trillion, six hundred forty-five billion, three hundred forty-one million, five hundred fifty-six thousand, seven hundred thirty-six".